Sixteen-year-olds on the job for more than nine hours straight, and sometimes over 48 hours in a week. Minors operating forklifts and motor vehicles or handling alcoholic beverages. Teenagers working late without adult supervision.

Those are some of the charges that have resulted in the state’s levying child-labor law fines against more than 100 companies, including national chains such as Dunkin’ Donuts and Subway.

In all, employers have racked up 3,550 violations and about $314,000 in civil fines since 2007, when the state began issuing citations. Child-labor laws in Massachusetts were tightened then following on-the-job deaths of several teenagers, including a 16-year-old who was killed after­ losing control of a golf cart at a Salem country club.

But enforcement citations appear to have dropped off dramatically in recent years, according to a Globe analysis. Two-thirds of the violations were recorded between 2007 and 2009, and the attorney general’s office — which eliminated five of 19 inspector positions from its fair labor division in 2011 — has not conducted a statewide sweep of shopping centers since 2008. Last year, the office reported a record low 199 infractions.

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Brad Puffer, a spokesman for Attorney General Martha Coakley, said robust enforcement and heightened public awareness have resulted in better compliance with child labor regulations. Puffer also noted the decline in violations could be partly attributed to a lower number of teenagers in the workforce because jobs are scarce in that age bracket.

“The economy has forced adults to take jobs historically held by teens,” he said. “That could change as the economy recovers and we will continue to ensure that all minors are treated fairly in the workplace.”

Marcy Goldstein-Gelb, executive director of the Massachusetts Coalition for Occupational Safety and Health,
said progress has been made in educating employers and teenagers about their rights and responsibilities.

MassCOSH, a workplace safety nonprofit, spearheaded reform of child labor laws. The regulations include restrictions on the hours and type of jobs permissible for workers between 14 and 17 years old and a requirement they obtain working permits that must be kept by their employers.

But Goldstein-Gelb said she is concerned about the large drop in the number of infractions and the lack of spot checks. Shortly after the labor laws were strengthened, sweeps at malls during the summer and holiday seasons, when many teens work, turned up numerous violations. The last one, conducted in summer 2008 at about nine retail outlets, netted more than 100 violations.

They included dozens for minors working without permits at the teen clothing retailer Hollister. The company paid about $4,700 in fines in 2008, on top of a $6,850 penalty in 2007 for citations related to teens working without permits and staying on the job after 10 p.m.

Hollister declined to comment.

“There is a lot more that needs to be done. We are still seeing hospitalizations of youths on the job,” Goldstein-Gelb said. “There are still vulnerable minors who are afraid to speak up about working conditions.”

The attorney general’s office hit businesses with some hefty penalties during the first few years of tougher regulations. Boston Sports Club took the top spot, with $40,000 in fines for about 345 violations in 2007 and 2008. Those infractions included minors working more than nine hours a day (the maximum for 16- and 17-year-olds), working before and after allowable hours, and working without permits.

In 2007, New England Sportservice, which runs concession stands at Comcast Center in Mansfield, received a $12,200 penalty for 121 violations, including 16- and 17-year-olds working more than nine hours a day and after 10 p.m.

Fines can add up quickly for employers with large staffs or those whose records were examined over several years. But individual citations — even for some potentially dangerous violations — are not that costly. For example, the state fined Hillis Corp. in Tewksbury $250 for twice allowing minors to operate forklifts and slapped the national restaurant chain Texas Roadhouse with a $250 penalty for permitting a teenager to handle alcoholic beverages.

Civil penalties allow up to $250 for the first violation, as much as $500 for the second, and a maximum of $2,500 for the third and each subsequent offense.

Many of the business officials interviewed by the Globe said they were unaware of the state’s child labor laws.

Ray Nadira, whose three Pronto Pizza restaurants north of Boston were fined $17,600 for minors working more than nine hours, without permits, and after hours, said he did not understand the various rules.

“I didn’t know there was a difference whether you’re 16 or 18,” Nadira said. “I never really paid too much attention to who was taking the extra shifts. You know, a lot of them are maybe the only people who work in the family. So if somebody’s good enough, we’d give them extra shifts.”

Franchisees for national brands such as Dunkin’ Donuts, Subway, and Domino’s appeared to have particular trouble following the law: They cumulatively racked up $67,625 in fines over the past six years.

Michelle King, a spokeswoman for Dunkin’ Brands Group, said the Canton company provides educational information to franchisees and restaurant managers on wage and hour laws, as well as child labor rules, but shop owners — who are independent of the corporation — make their own day-to-day operating decisions.

“We understand that some of the past incidents of child labor citations of franchisees in Massachusetts ranged from teens failing to clock out to teens working later than permissible and more than the maximum number of hours allowed per day,” King said. “Dunkin’ Donuts and its franchisees have worked cooperatively with the office of the attorney general of Massachusetts to resolve these situations.”

Despite the state’s efforts to increase awareness of child labor laws, some big companies still fall far short of compliance. The Arbors, which runs six assisted-living facilities in Massachusetts, racked up $13,400 in fines this year for 118 violations over the past three years, including having minors on duty for more than nine hours a day and past 10 p.m.

Westwood Management, which operates The Arbors, refused to discuss how the violations transpired for so long without being corrected. But Kevin V. Maltby, an attorney for the business, said the company “fully cooperated” with officials and the matter was “resolved to the satisfaction of the attorney general in January 2013.”

Puffer, of Coakley’s office, said the agency plans to hire additional inspectors for the fair labor division later this year. They will be responsible for investigating a wide range of issues, including wage and hour and child labor infractions. Meantime, he said, the state recently reached settlements with some businesses, including a $158,000 deal last fall with national restaurant chain Ruby Tuesday to resolve claims of child labor violations.

Many cases start with tips and complaints. While teen employment rates have slumped in recent years, some minors, particularly immigrants, do not want to speak out about violations for fear of risking their jobs, said Laurence Louie, youth coordinator for the Chinese Progressive Association in Boston’s Chinatown.

“Many immigrant youth rely on work for survival. A lot are working at places like restaurants where they work long hours and are sometimes underpaid,” Louie said. “But they just accept these conditions to some extent.”

Jariel Soto, a 17-year-old Boston resident who works with MassCOSH to help educate young people about job safety and health, said many teens won’t complain because they need the money and know they are easily replaced.

“They feel as if they don’t do [the work], someone else will. They see so many teens looking for a job,” Soto said.

Workplace safety advocates say it’s important — especially when people are competing for a limited number of jobs — that officials make random visits to ensure employers follow the law. There are still hundreds of teens treated at Massachusetts hospitals each year for work-related injuries — 324 such minors visited emergency rooms in 2010, the latest figures available from the state.

Moreover, advocates say, the state should routinely check in with employers who have already been fined. The lack of follow-up could help explain why only 20 of the 3,550 violations are listed as second offenses.

Puffer doesn’t view it that way.

“We have seen that a combination of outreach, education, and enforcement has been effective in ensuring that all businesses play by the same rules and are familiar with what the law says about employing young workers,” he said. “We hope that the lack of second offenses is evidence that our effort­ is working.”

Goldstein-Gelb, of MassCOSH, said she understands the agency’s budget constraints but without follow-up it’s hard to know whether fines are deterring companies from reoffending.

“If an employer has violated once,” Goldstein-Gelb said, “there is a chance they’ll do it again.”

Todd Wallack of the Globestaff and Globe correspondent Alyssa Edes contributed to this report. Jenn Abelson can be reached at abelson@globe.com.

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